1. Field of the Invention
The present invention relates to a drive assembly for rolls in a roll laminator, with at least one of the rolls being displaceable. More particularly, the drive assembly includes an endless driving element and several idler sprocket wheels, with one of the idler sprocket wheels positioned to enable the endless drive element to maintain a substantially constant path length as the displaceable roll is moved upward.
2. Description of the Prior Art
Feed roll apparatus driven by a chain, utilizing idler sprockets and having displaceable rolls is known to the art. This type of apparatus has the disadvantage of requiring the use of a second chain to drive the displaceable roll and/or having to provide substantial slack in the chain to allow for movement of the roll and including a tensioning device to compensate for the slack (U.S. Pat. No. 3,272,026 to J. K. Hale). What is needed is an assembly in which the roll is displaceable without the need for a second chain or a tensioning device.